7th Grade Math

9/22/14

Monday: Bell work

• Jimmy was diving in the ocean. He dove 6.2 miles. Then he found a shark. He darted upward 2 miles then fought him off. He then dived 5.12 miles again. How many miles is he below sea level?

(Mitch Crockett)

Solve–7.5t + 4 = -26

TURN IN ANY LATE HOMEWORK!!

Lesson

• ... solve real-world problems involving the addition, subtraction, multiplication, and/or division of rational numbers? (7.NS.3)

Word Wall Quiz

• Match and/or Fill in the blank for each term

• Words are only used one time.

• For the matching – write the letter beside the number

Remember

Multiplying Fractions

N x N = N D D D

6 X 8 = 487 11 77

• Multiply straight across

Dividing Fractions

N ÷ N = N D D D*multiply the reciprocal N x D = N D N D 6 ÷ 8 = 48 6 x 11 = 66

7 11 77 7 8 56

Multiplying / Dividing Mixed Numbers

• Change to mixed numbers to improper fractions and then multiply or divide.

Multiplying Fractions using Area Model

• http://www.libertyunion.org/userfiles/1039/Classes/3543/Unit%202%20Lesson%203.pdf

• http://www.cpm.org/pdfs/skillBuilders/MC/MC_Multiplication_of_Fractions.pdf

Exit / Closure

• Tommy said that 4 + 2 x = -24 x is 14.

• Justify whether Tommy is incorrect or correct.

• ***Be ready to explain your answer to a partner.

Tuesday: Bell Work

1. Can you relate fractions to the real world?

2. Where have you used or seen fractions, specifically the

multiplication of fractions ?

VocabularyLooking the word wall.

Pick 1 word that you can apply to fractions.

Be prepared to justify why you choose that word.

Essential Question

• Can I solve real-world problems involving the addition, subtraction, multiplication, and/or division of rational numbers? (7.NS.3)

Multiplying Fractions using Area Model

Garden Task

• 1. Work on the task individually in the indicated corner.• 2. Combine and work as a group of 4 to solve and model

the garden task in the middle of the 4-corner poster.• 4. At least two groups will present. While a group is

presenting, write down questions you can ask the group.EQ: Can I solve real-world problems involving the addition,

subtraction, multiplication, and/or division of rational numbers? (7.NS.3)

Group WorkGroup Work

Student 1

Student 3Student 4

Student 2

Exit Ticket

Solution

1260

Solution

1260

•Essential Question: CAN I solve real-world problems involving the addition, subtraction, multiplication, and/or division of rational numbers? (7.NS.3)

Wednesday: Bell Work

1) a + 5.8 = 26.6 4.5

2) X + 2.4 = 15.4 2

Solve the equationsHave homework on desk ready to check

Adding Fractions

• Adding Fractions • There are 3 Simple Steps to add fractions:• Step 1: Make sure the bottom numbers (the

denominators) are the same • Step 2: Add the top numbers (the

numerators), put the answer over the denominator

• Step 3: Simplify the fraction (if needed)

Subtracting Decimals

• Follows the same pattern as adding except you subtract the numerators.

Exit / Closure

In math, why is it important to have the same denominator when adding and subtracting decimals?

Thursday: Bell Work

• Joey, Keith, and Eli have a combined height of 7 meters. If Joey is 2.31 meters tall and Eli is 2.6 meters tall, how tall is Keith?

• *Write and solve the equation. The variable cannot be in the answer.*

Lesson

• ... solve real-world problems involving the addition, subtraction, multiplication, and/or division of rational numbers? (7.NS.3)

• Critical Thinking Activity • Dan worked as a volunteer for a total of 103

hours in 21 days. He worked about the same number of hours each day. Which is the best estimate of the number of hours Dan worked as a volunteer each day?– a) 3– b) 4– c) 5– d) 6

• Constructed Response • Amy is in charge or ordering new computers for her

classroom. If each computer costs $1256.33 and Amy needs to order 5 computers, about how much money will Amy need?

• Amy says she will need about $5,000.00 for her new computers. She shows her work:

• $1256.33 rounds to $1000.00 and 1000.00 times 5 = $5,000.00

• Did Amy round correctly for this situation? Defend you answers using words and examples.

Adding / Subtracting Mixed Numbers

Subtracting Mixed Numbers

Solving Equations with Fractions

My.hrw.com

Exit / Closure

• What is the purpose of converting mixed numbers to improper fractions?

Friday: Bell Work1) James works at an Indian sweet shop. He needs to fill boxes with 0.3 kilograms of coconut candy each. If he has 8 kilograms of coconut candy, how many boxes can he fill?

Write and solve the equation. The variable cannot be in the answer.*

Lesson

• ... solve real-world problems involving the addition, subtraction, multiplication, and/or division of rational numbers? (7.NS.3)

Exit / Closure

• What is the importance of checking your work in math?

• Discuss with a partner

Wednesday: Bell Work

Problem Solving with Scientific Notation

• You know that a number is in scientific notation when it is broken up as the product of two parts. The first part, the coefficient, is a number between 1 and 10. The second part is a power of ten. For example, 3 500 is expressed in scientific notation as

• 3 500 = 3.5 x 10^3• ↑ ↑• coefficient power of ten • How can you do calculations with numbers expressed in

scientific notation? First consider addition and subtraction, then multiplication and division.

Addition and Subtraction

• Like Exponents: If two numbers have like exponents, simply add or subtract the coefficients and keep the same power of ten. Convert the sum or difference to scientific notation if needed. For example:

• a. (9.0 x 10^3) + (2.5 x 10^3) = 11.5 x 10^3 = 1.15 x 10^4

• b. (4.4 x 10^5) - (2.2 x 10^5) = 2.2 x 10^5

• Unlike Exponents: If two numbers have unlike exponents, they must be made the same before the numbers can be added or subtracted. Move decimal points as needed to compensate for changes you make to the exponents. For example:

• a. (3.0 x l0^5 m) + (2 x 10^4 m) = (30 x 10^4 m) + (2 x 10^4 m) = 32 x 10^4 m = 3.2 x l0^5 m

• b. (6.0 x 10^6 kg) - (4 x 10^7 kg) = 6.0 x 10^6 kg - 0.4 x 10^6 kg = 5.6 x 10^6 kg

• Unlike Units: To add and subtract numbers in scientific notation with unlike units, you need to know about metric prefixes. (Look in your text for a list of them.) To begin, convert measurements to a common metric unit. Then make powers of ten the same. Finally you can add or subtract. For example:

• a. 6.1m + 24km = 6.1m + 2400m = 2406.1 m• b. (4.62 x 10^2 L) + (2.1 mL) = 46.2 mL + 2.1 mL =

48.3 mL = 4.83 x 10^1 mL

Multiplication and Division

• Numbers expressed in scientific notation don't need to have the same exponents to be multiplied or divided. Just use the following rules.

• Multiplication: To multiply two or more numbers in scientific notation, multiply the coefficients and add the exponents. Units are multiplied. For example:

• a. (4 x 105 m)(2 x 106 m) = 8 x 1011 m2 • b. (2 x 10-2 m)(4 x 106 m) = 8 x 104 m2 • c. (3 x 103 kg)(5 x 106 m) = 15 x 109 kg. m =

1.5 x 1010 kg. m

• Division: To divide two or more numbers in scientific notation, divide the coefficients and subtract the exponent of the denominator from the exponent of the numerator. Units are divided. For example:

• a. (9 x 106 m) / (3 x 102s) = 3 x 106-2m/s = 3 x 104m/s

• b.(4 x 103g) / (2 x 10-2L) = 2 x 103-(-2)g/L = 2 x 105g/L

Try These: Exit Ticket• 1. (3 x 103) + (2 x 103) • 2. (2 x 10-7 m) + (3 x 10-7 m) • 3. (8 x 10-8 m2) – (3 x 10-8 m2)• 4. (3.8 x 10-7 m2) – (2.8 x 10-7 m2)• 5. (5.0 mm) + (2 x 10-4 m)• 6. (6.2 km) – (3 x 102 m)• 7. (2 x 105 m)(3 x 106 m)• 8. (5 x 10-4 m)(4 x 10-2 m)• 9. (1.50 x 10-7 m)(2.50 x 1015 m)• 10. (9 x 108 kg)/(3 x l04 m2)• 11. (2.4 x 105 kg)(3 x 104 m) / (4 x 10-2 s2)